Measure the area behind your mattress to determine the preferred size for your headboard. Purchase enough foam core boards to create the overall height and width of the headboard.
Cut the foam core boards to fit the dimensions of the headboard or to create a special design. To cut the boards, measure and mark the cut lines with a pencil. Align a straight edge along the pencil mark to make a straight cut, and then drag the sharp point of a utility knife at a 45 degree angle along the foam core board. Make a second pass with the utility knife to cut all the way through the foam core. Trace curved cut lines with a pencil, and then drag the angled utility knife over the lines twice.
Arrange the foam core boards in the desired configuration for your headboard. Tape the seams where the boards meet with strips of duct tape on the back and on the front of the foam core board.
Measure and cut a section of fabric to fit over the face and to wrap 4 inches around the backside perimeter of the connected foam core boards. Place the fabric face down on a flat surface.
Center the connected foam core boards on top of the fabric. Pull the edges of the fabric up over the edges of the board. Duct tape the fabric to the backside of the foam board, one edge at a time. Fold the corners as flat as possible around the headboard.
Cut a strand of ribbon to fit around the perimeter edge of the headboard. Heat up the glue gun and insert a glue stick. Glue the ribbon in place around the edge of the foam core headboard.
Attach the headboard to the wall using interlocking adhesive strips. Place an interlocking strip every 6 inches along the height and the width of the headboard for maximum adhesion.